Allow domain-like as URL location input (#35756)

* Allow domain-like as URL location input

Before this patch, domain with subdomain (e.g. book.servo.org) won't be
treated as URL location.

This patch retifies that by adding Firefox's location bar behavior:

  - book.servo.org is URL location
  - book.servo.org. is URL location
  - .book.servo.org is not URL location

Fixes #35754.

Signed-off-by: Kafji <k@kafji.net>

* Chain location input interpretation attempts

Signed-off-by: Kafji <k@kafji.net>

---------

Signed-off-by: Kafji <k@kafji.net>

ports/servoshell/parser.rs

@@ -63,13 +63,35 @@ pub fn get_default_url(
 /// interpret the string as a search term.
 pub(crate) fn location_bar_input_to_url(request: &str, searchpage: &str) -> Option<ServoUrl> {
     let request = request.trim();
-    ServoUrl::parse(request).ok().or_else(|| {
-        if request.starts_with('/') {
-            ServoUrl::parse(&format!("file://{}", request)).ok()
-        } else if request.contains('/') || is_reg_domain(request) {
-            ServoUrl::parse(&format!("https://{}", request)).ok()
-        } else {
-            ServoUrl::parse(&searchpage.replace("%s", request)).ok()
-        }
-    })
+    ServoUrl::parse(request)
+        .ok()
+        .or_else(|| try_as_file(request))
+        .or_else(|| try_as_domain(request))
+        .or_else(|| try_as_search_page(request, searchpage))
+}
+
+fn try_as_file(request: &str) -> Option<ServoUrl> {
+    if request.starts_with('/') {
+        return ServoUrl::parse(&format!("file://{}", request)).ok();
+    }
+    None
+}
+
+fn try_as_domain(request: &str) -> Option<ServoUrl> {
+    fn is_domain_like(s: &str) -> bool {
+        !s.starts_with('/') && s.contains('/') ||
+            (!s.contains(' ') && !s.starts_with('.') && s.split('.').count() > 1)
+    }
+
+    if !request.contains(' ') && is_reg_domain(request) || is_domain_like(request) {
+        return ServoUrl::parse(&format!("https://{}", request)).ok();
+    }
+    None
+}
+
+fn try_as_search_page(request: &str, searchpage: &str) -> Option<ServoUrl> {
+    if request.is_empty() {
+        return None;
+    }
+    ServoUrl::parse(&searchpage.replace("%s", request)).ok()
 }